3-alkoxycyclobutanols



United States Patent 3,379,770 3-ALKOXYCYCLOBUTANOLS Edward U. Elam andJames C. Martin, Kingsport, Tenn., assignors to Eastman Kodak Company,Rochester, N .Y-, a corporation of New Jersey No Drawing. Filed Nov. 27,1964, Ser. No. 414,474 Claims. (Cl. 260-611) ABSTRACT OF THE DISCLOSUREThe chemical or catalytic reduction of 3-alkoxycyclobutanones providethe corresponding 3-alkoxycyclobutanols. The 3-alkoxycyclobutanols areuseful as chemical intermediates for example, in the preparation ofcarboxylic ester derivatives of the 3-alkoxycyclobutanols, as well assolvents, plasticizers, hydraulic fluids, etc.

DISCLOSURE This invention relates to novel chemical compounds and theirprepartion. More particularly, this invention relates to novel3-alkoxycyclobutanols of the formula:

R --OHCH-OH a o- H- R R1 their preparation by the reduction of3-alkoxycyclobutanones and to carboxylic acid esters of the3-alkoxyclobutanols.

In the above formula for the novel 3-alkoxycyclobutanols of ourinvention, the substituent R can be hydrogen or lower alkyl and thesubstituent R is alkyl or aralkyl. The substituents R and R when takensingly, are alkyl and, when taken collectively with the carbon atom towhich they are attached, represent a saturated carbocyclic ring having 4to 8 ring carbon atoms.

R when lower alkyl, is typically alkyl of 1 to about 5 carbon atoms suchas methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,tert-butyl, n-pentyl, etc. R is typically substituted or unsubstitutedalkyl of l to about 18 carbon atoms or aralkyl of 7 to about 19 carbonatoms and, when alkyl, is preferably alkyl of 1 to about 8 carbon atomssuch as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl,hexyl, heptyl, octyl, 2-ethylhexyl, etc. R when aralkyl, is typicallybenzyl, diphenylmethyl, triphenylmethyl, (p-tolyl)methyl, etc. R and Rwhen alkyl, are typically alkyl of 1 to 18 carbon atoms and arepreferably alkyl of 1 to about 8 carbons such as methyl, ethyl, propyl,isopropyl, butyl, isobutyl, sec-butyl, pentyl,

hexyl, octyl, 2-ethylhexyl, etc. R and R when taken collectively withthe carbon atom to which they are attached to represent a saturatedcarbocyclic ring of 4 to 8 carbon atoms, typically represent carbocyclicrings such as cyclobutylidene, cyclopentylidene, cyclohexylidene,cycloheptylidene, and cyclooctylidene.

Examples of some of the preferred 3-alkoxycyclobutanols of our inventioninclude compounds such as 2,2-dimethyl-3-methoxycyclobutanol; 2,2dimethyl-3-ethoxycyclobutanol; 3 -benzyloxy-2,Z-dimethylcyclobutanol; 2-butyl-2-ethyl-3-butoxycyclobutano1; 2,2,4 trimethyl-3-ethoxycyclobutanol; 2,2 dimethyl-3-(2-ethylhexyloxy)- cyclobutanol;1-ethoxy-3-hydroxyspiro[3.5] -nonane; 3-isobutoxy-Z,Z-dioctylcyclobutanol; 3-benzyloxy-4-ethy-l-2,Z-dimethylcyclobutanol; etc.

The esters of our invention can be represented by the formulae:

wherein R R R and R are as hereinbefore defined; R is the residue of anorganic monocarboxylic acid and R is the residue of an organic dioicacid.

R typically has 1 to about 18 carbon atoms and preferably has 1 to about8 carbon atoms. Examples of monocarboxylic acid residues represented byR are those from alkanoic acids such as formic acid, acetic acid,propionic acid, butyric acid, isobutyric acid, valeric acid, etc.;unsaturated acids such as acrylic acid, methacrylic acid, oleic acid,etc.; substituted alkanoic acids such as trichloroacetic acid, etc.; andsubstituted or unsubstituted aromatic acids such as benzoic acid,p-nitrobenzoic acid, etc.

R typically has 1 to 18 carbon atoms and preferably contains 1 to about8 carbon atoms. Examples of diotic acid residues represented by R arethose from acids such as carbonic acid and from organic dicarboxylicacids, e.g., alkanedioic, alkenedioic or arylenedioic acids, such asmaleic acid, fumaric acid, succinic acid, adipic acid, phthalic acid,terephthalic acid, isophthalic acid, 3,3'-thiodipropionic acid; etc.

Examples of some of the preferred 3-alkoxycyclobutanol esters of ourinvention include compounds such as 3-ethoxy-2,Z-dimethylcyclobutylacetate; bis(3-ethoxy-2, Z-dimethylcyclobutyl)adipate; 3ethoxy-2,2-dimethylcyclobutyl decanoate; 3methoxy-2,2-dimethylcyclobutyl benzoate; 3 ethoXy-2,2-dimethylcyclobutyltrichloroacetate; bis(3-ethoXy-2,Z-dimethylcyclobutyl)maleate; bis-(3-ethoxy-2,2-dimethylcyclobutyl fumarate; 3-butoxy-2,- 2dimethylcyclobutyl ethylcarbonate; 3-methoxy-2,2dimethylcyclobutylacetate; 3-ethoxy-2,Z-dimethylcyclobutyl p-nitrobenzoate; 3-isobutoxy2,2 dioctylcyclobutyl methacrylate; 3-ethoxy 2,2 dimethylcyclobutylacrylate; 3-ethoxy 2,2 dimethylcyclobutyl oleate; bis(3-butoxy-2,Z-dimethylcyclobutyl)-3,3'-thiodipropionate; etc.

The novel 3-alkoxycyclobutanols of our invention can be prepared by thereduction of a 3-alkoxycyclobutanone. The latter compounds can beprepared by the cycloaddition of a ketoketene and an alkyl vinyl ether.The reaction is carried out, e.g., by heating equimolar amounts of aketoketene such as dimethyl ketene and an alkyl vinyl ether such asethyl vinyl ether in an inert polar solvent as illustrated in Martin,US. patent application, Ser. No. 276,177, filed Apr. 29, 1963, and nowPatent No. 3,312,- 741.

The reduction of the 3-alkoxycyclobutanone can be carried outchemically, i.e., with a chemical reducing agent, or catalytically byhydrogenation of the 3-alkoxycyclobutanone in the presence of ahydrogenation catalyst.

When the reduction is carried out chemically, it is prefera'blyperformed in a conventional manner with a boron containing chemicalreducing agent such 'as an alkali metal borohydride, analkoxyboro'hydride or an amineborane; with an alkali metal hydride suchas lithium, sodium or potassium aluminum hydride or with an aluminumalkoxide such as aluminum isopropoxide. Especially preferred as chemicalreducing agents are the 'alkali metal borohydrides, e.g., sodiumborohydride. The reduction is preferably carried out in an aqueousmedium when an alkali metal borohydride is employed as the reducingagent.

In operations of a commercial size, it is preferred to conduct thereduction of the 3-'allsoxycyclobutanone catalytically by contacting the3-alkoxycyclobutanone with hydrogen in the presence of a hydrogenationcatalyst. Suitable catalysts include conventional supported andunsupported hydrogenation catalysts such as iron, nickel,

cobalt, ruthenium, palladium, platinum, copper-chromium oxide, etc.Nickel or ruthenium containing hydrogenation catalysts, e.g., Raneynickel or supported ruthenium, are preferred.

The catalytic reduction of the 3-alkoxycyclobutanone is preferablycarried out at elevated temperature and superatmospheric pressure,though temperatures as low as 25 C. and pressures as low as 1 atmosphereare suitable. Suitable temperatures and pressures are from about 25 C.to about 200 C. and about 1 atmosphere to about B00 atmospheres.Preferred temperatures are from about 50 C. to about 150 C. andpreferred pressures are from about 10 to about 150 atmospheres.

The cfollowing examples illustrate the preparation of the novelcompounds of our invention.

Example 1 1/4 NaBH; 0530 CH; onto CH3 (H; CH3

A solution of 200 g. of 2,2-dimethyl-3-methoxycyclobutanone in 300 ml.of methanol was hydrogenated over 20 g. of 5% ruthenium on carbon powderat 100 C., 3000 p.s.i. After reduction was complete, the product wasfiltered and distilled to give 158.1 g. (74% yield) of2,2-dimethyl-3-rnethoxycyclobutanol, BJP. 95-96" C. (25 mm.), n1.4470-1.4472.

Example 3 *0 H OH 1/4 NaBH4 CnHsO---J CH3 O HEO CH3 A solution of 30.5g. (0.8 mole) of sodium borohydride in 300 ml. of water was stirredvigorously and treated with 280 g. of2,2-dimethyl-3-ethoxycyclobutanone. 'An ice bath was used to keep thetemperature below 50 C. during the addition. The mixture was stirred atroom temperature overnight, and worked up as described in Example 1. Theyield of 2,2-dimethyl-3-ethoxycyclobutanol, 'B.P. 97 C. (22 mm.), n1.4460, was 223 g.

Example 4 -O Ru OH H: I C2H5O CH3 CaHgO #011 H3 CH3 A solution of 250ml. of 2,2-dimethyl-3-ethoxycyclobutanone in 250 ml. of ethyl alcoholwas hydrogenated over 20 g. of 5% ruthenium on carbon at 75 C., 3000p.s.i. The product was filtered and dis-tilled to give2,2-dimethyl3-ethoxycycldbutanol, BJP. 96-97 C. (22 mm.) in 60% yield.

Example '5 O N1 OH H: CaH5O- CH3 02H) 3 A solution of ml. of2,2-dimethyl-3-ethoxycyclobutanone in 75 ml. of ethanol was hydrogenatedover 10 g. of 'Raney nickel at C., 3000 p.s.i. The yield of2,2-dimethyl-3-ethoxycyclobutanol, BxP. 97-98 (25 mm.) Was 70%.

Under the general conditions of Example 2, the following cyclobutanonesare reduced to the corresponding 'cyclobutanols:

The 3-alkoxycyclobutanols of our invention are particularly useful aschemical intermediates, e.g., for the preparation of esters of3-alkoxycyclobutanols. The novel carboxylic acid esters, of the3-alkoxycyclobutanols are prepared by conventional esterificationmethods. The esterification can be carried out by contacting the3-alkoxycyclobutanol with a carboxylic acid, an acid halide of acarboxylic acid or a carboxylic acid anhydride, preferably in thepresence of an acidic or basic esterification catalyst. A preferredmethod for preparing the novel esters of our invention is to contact the3-alkoxycyclobutanol with an acid'halide, eg., an acid chloride, in thepresence of a tertiary amine, e.g., pyridine.

Another preferred method for the preparation of the esters is to contactthe 3-alkoxycyclobutanol with the carboxylic acid in the presence of anaryl sulfonic acid, e.g., p-toluenesulfonic acid.

The following examples illustrate the preparation of the novelcarboxylic acid esters of 3-alkoxycyclobutanols of our invention.

Example 8 CHtCOOH C|H|O CH:

I odont J 4* Hi CgHgO OH:

A mixture of 71 g. of 2,2-dimethyl-3-ethoxycyclobutaml, 100 ml. ofacetic acid, 100 ml. of toluene, and 0.5 g. of p-toluenesulif onic acidwas refluxed under a Dean-Stark trap until no {more water came over. Theproduct was treated with 5 g. of potassium acetate and ;distilled togive 76 g. of 2,2-dimethyl-3-ethoxycyclobutyl acetate, B.P., 95-10l C.

Example 9 O (CHah 0:]-

6 Analysis.Ca1cd. for c m o Sapon. equiv., 198. Found: Sapou. equiv.,195.

Example 10 mil iC HI C IHLO i c H:

A mixture of 71 g. (0.5 mole) of 2,2-dimethyl-3-ethoxycyclobutanol, 103g. (0.6 mole) of decanoic acid, ml. of toluene, and 2 g. ofp-toluenesulfonic acid was refluxeld under a Dean-Stark trap until allof the water had been removed. The product was stripped of solvent andthe residue distilled in acyclic falling film molecular still to give2,2-dimethyl-3-ethoxycyclobutyl decanoate, B.P. 85 (70,), hp 1.4460.

Analysis.--Calcd. for C H O: Sapon. equiv., 298. Found: Sapon. equiv.,289.

Example 11 C1130 CH] A solution of 13 g. of3-methoxy-2,Z-dimethylcyclobutanol in ml. of pyridine was treated with15 g. of benzoyl chloride. The mixture was allowed to stand overnight,filtered from precipitated pyridine hydrochloride, and washed withwater. The solvent was evaporated on the steam bath. The residue (23 g.)had n 1.5081. It was determined to be very pure by gas chromatography.

Example 12 Under the general conditions of Example 11, the followingcyclobutanols and acid halides give the products shown:

Cyclobutanol Acid Halide Product 1? OH H 0 C C 01: l CltCCC] C1 n0-( a)iC: a):

ll OH (I? (I? OCCH=CHCO- ClC CH=CHC C1 J I CaHs s): J B (C :):(C :)z 01H OH (I? w 0 C O CIHI ClC OCIH! i l- 4 o 5): 9 t):

II OH r0 C CH: l BrCCHa i CH|O-(CH3): CH|O. -(CHI)I ii 0H p cm) -ocno,

ClC-Q-NO: CI s 1): CaHuO o 0 ll OH H (CsHn) 0CC=CH1 CIC C=CH2 i CH;(CHfllCHO-(CaHn): CH: (CHI)ICHO Cyclobutanol Acid Halide Product i l OHO C CHICHI O 0 11 CaHnO CEBU-(CH3); C10 CHlCHISCHICHIG C1 (CH3): 2

ii OH OO(OHz)1CH CzHO----(CH3): CH;(CH!)7CH=CH(CH1)1COC1 CtHsO CH3)! (H)a 1 l CHI Example 13 OH 1 CHFCHCO OH --r CaHrO O:

i O CH=CH:

cyclobutanol, 500 ml. of benzene, 72 g. (1 mole) of acrylic 2 acid, 1 g.of hydroquinone monomethyl ether and 5 g. of p-toluenesulfonic acid wasrefluxed under a 6-in. Vigreux column equipped with a Dean-Stark watertrap. After water removal was complete, the solution was washed withwater, 10% sodium carbonate solution, water and dried over anhydroussodium sulfate. This solution was distilled from cuprous chloridethrough a 6-in. Vigreux column to give 80.2 g. of3-ethoxy-2,2-dimethylcyclobutyl acrylate, B.P. 80-83 C. (5 mm).

The novel 3-alkoxycyclobutanols are useful, not only for the preparationof esters, but also as solvents, plasticizers, e.g., for vinyl resins,hydraulic fluids, etc. The 3-alkoxycyclobutanol esters of unsaturatedacids are useful in the preparation of copolymers with other unsaturatedcompounds and the 3-alkoxycyclobutanol esters with saturated car-boxylicacids are useful as plasticizers, solvents, etc.

The following example illustrates the use of one of the esters of ourinvention as a plasticizer for a vinyl halide resin.

Example 14 A plastic composition containing 66 parts of bis(2,2-dimethyl-3-eth0xycyclobutyl)adipate in polyvinyl chloride was preparedby milling the components together on heated rolls. The resultingplastic was tough, flexible and had good mechanical properties.

The following example illustrates the preparation of a copolymercontaining one of the esters of our invention.

Example 15 A copolymer containing 3-ethoxy-2,2-dirnethy1- cyclobutylacrylate and 70% acrylonitrile was prepared by conventionalpolymerization techniques. It had a sticking temperature of 160 C. andcould be cast into tough films and spun into strong fibers.

Although the invention has been described in detail with particularreference to certain preferred embodiments thereof, variations andmodifications can be eflected within the spirit and scope of theinvention as described hereinbefore and as defined in the appendedclaims.

We claim:

1. A compound having the formula:

R -OH-CH-OH R O--CH- --rt wherein:

R is selected from the group consisting of (a) hydrogen and (b) loweralkyl;

R is selected from the group consisting of (a) alkyl of l-18 carbonatoms and (b) aralkyl of 7-19 carbon atoms;

R and R when taken singly, are alkyl of l-18 carbon atoms and, whentaken collectively with the carbon atom to which they are attached,represent a saturated carbocyclic ring of 4 to 8 ring carbon atoms.

2. A compound having the formula References Cited UNITED STATES PATENTS7/ 1954 Schlesinger 260-617 X 6/1965 Elam et al. 260-617 BERNARD HELFIN,Primary Examiner.

